Investigation of expression and mobilization characteristic of endothelial progenitor cells in renal cell carcinoma

Objective To investigate the endothelial progenitor cells (EPCs) in the peripheral blood (PB),tumor tissue (TT) and adjacent nonmalignant tissue(AT) of mice with renal cell carcinoma progression (RCC) and explore mobilized characteristic and mechanism in RCC.Methods Male,BALB/c nude mice were randomly divided into three groups:RCC group; sham group and normal group.Mice were killed respectively at days 21,28,35,42,49 after implant tumor cells,blood and tissue samples were harvested.Numbers of Circulating endothelial progenitor cells,plasma levels of vascular endothelial growth factor and stromal cell-derived factor-1,numbers of EPCs and mRNA (VEGF and SDF-1) expression in normal tissue (NT),sham tissue (ST),AT and TT were evaluated.Results CEPCs levels and plasma angiogenic factor (VEGF and SDF-1) were higher in PB of the RCC group than those in the normal and sham groups (P ＜ 0.05)and there are a positive correlation between them (r1 =0.584,r2 =0.579).EPCs levels in AT were significantly higher than those in TT and NT (P ＜ 0.05),which were positively correlated with CEPCs levels (r =0.857).VEGF and SDF-1 expression in AT was significantly higher compared to that in TT and NT (P ＜ 0.05),which were positively correlated with that in plasma (r1 =0.618,r2 =0.421).Conclusion VEGF and SDF-1 in adjacent tissue play key role in entire mobilized process of EPCs. Key words: Renal cell carcinoma;  Circulating endothelial progenitor cells;  Endothelial progenitor cells;  Angiogenic factors